1. Field of the Invention
The present invention relates generally to a variable displacement wobble plate type compressor with a wobble angle control unit, capable of automatically changing a compressor displacement in response to a change in a refrigerating load in an air-conditioning system in which the variable displacement wobble plate type compressor is accommodated, and more particularly, relates to a wobble angle return system incorporated in a variable displacement wobble plate type compressor for promoting the return of a wobble plate from the least wobble angle position, i.e., an erect position of the wobble plate, to a larger wobble angle position thereof, i.e., an inclined position of the wobble plate.
2. Description of the Related Art A pending U.S. patent application Ser. No. 856,760 of the same assignee as the present patent application, filed on Apr. 28, 1986, discloses a variable displacement wobble plate type compressor with a wobble angle control unit improved so as to achieve a smooth return of the wobble plate from the least inclined position thereof to a fully inclined position thereof. The compressor disclosed in the pending U.S. patent application Ser. No. 856,760 can be operated at a wide displacement range from the extremely small displacement state to the full displacement state, and therefore, the compressor can be operated so that the compressor displacement is always set at an optimum condition in accordance with a change in the refrigerating load applied to the air-conditioning system. The inventors of the present application have continued their investigation into the performance of a wobble angle control unit of a variable displacement wobble plate type compressor on the basis of the control unit of the pending U.S. patent application Ser. No. 856,760. As a result, the present inventors of the present application succeeded in contriving another wobble angle control unit of a variable displacement wobble plate type compressor, which unit is definitely different from that disclosed in the pending U.S. patent application Ser. No. 856,760, and has a function of promoting a smooth return of the wobble plate from the least angle position to a larger angle position.